Oleanolic acid (OA), also known as caryophyllin, is a type of pentacyclic triterpenoids. It is extracted from the leaves and fruits of Oleaceae, Gentianaceae, Rubiaceae, Amaranthaceae, and the like, and is mainly present in free form and (or) in combination with saccharides. Many scientists, domestic and overseas, have conducted extensive research on pentacyclic triterpenoids. According to the literature, oleanolic acid and derivatives or analogs thereof exhibit a variety of biological activities, such as anti-inflammation, antitumor, antivirus, immunoregulation, inhibition of platelet aggregation, hypolipidemic, liver protection, kidney protection, anti-HIV, etc. (LI, Yingxia et al., An oleanolic acid-lactose conjugate, the preparation process and use thereof, [P] CN 1414012 A.2003; ZHANG, Yihua et al., An oleanolic acid derivative, the preparation process and use thereof, [P] CN 102070697 A.2011; Lin, Z. H.; Zhang, Y.; Zhang, Y. N.; Shen, H.; Hu, L. H.; Jiang, H. L.; Shen, X. Oleanolic acid derivative NPLG441 potently stimulates glucose transport in 3T3-L1 adipocytes via a multi-target mechanism. Biochemical Pharmacology. 2008. 76:1251-1262; Chen, J.; Gong, Y. C.; Liu, J.; Hua, W. Y.; Zhang, L. Y.; Sun, H. B. Synthesis and biological evaluation of novel pyrazolo[4,3-b]oleanane derivatives as inhibitors of glycogen phosphorylase. Chemistry & Biodiversity. 2008. 5: 1304-1312).
